Context
TFT
TFT is an 8-player free-for-all drafting tactics game in which the player recruits powerful champions, deploys them, and battles to become the last player standing.
When acquired, a champion starts as a 1-Star. Three of the same 1-Star champion can be combined to create a stronger 2-Star champion. Three of the same 2-star champions can be combined to create an even stronger 3-Star champion.
Champions have one origin and one class, with a few exceptions. Satisfying the origin or class conditions grants bonus effects to the entire team or to the champions of the respective origin or class.
A champion can hold up to 3 items at a time.
Set 4
In Set 4: Fates, Chosen champions occasionally appear in a player's shop. Player can have at most one Chosen champion in the game.
Chosen champions come with some extra power:
One of their traits (origin or class) is "Chosen" and counts as 2 of that trait.
They gain 200 bonus health.
They also gain a unique bonus stat, based on the champion. (wiki)
Content
There are 14 columns, most of them are explained intuitively.
I'll explain 2 more complicated columns:
Traits column: json data - key: value
key: Trait name
value: Number of units with this trait
Units column: json data - key:value
key: Unit name
value: Dictionary 'items': items_array, 'stars': number of unit's stars
Inspiration
Most used items/champions
Most used items/champions in different versions
Matches with 3-stared 4/5 cost units